1. Field of the Invention
The present invention relates to an apparatus and method of controlling a robot for automatically driving a motorcar in a simulation of car travel in which a driving wheel of the car is placed on a roller of a chassis dynamometer. With the car on the chassis dynamometer, dynamic performance tests of the motorcar can be conducted within a room.
2. Description of the Prior Art
A simulation of actual car travel driving by means of a chassis dynamometer has been used for dynamic performance testing of motorcars. Recently a motorcar driving robot (hereinafter referred to as a robot) adapted to individually drive a plurality of actuators by use of, for example, oil pressure, air pressure, DC servo motors, and the like, conducting stepping operations of an accelerator pedal, brake pedal, clutch pedal and the like of the automobile, as well as changeovers of a shift lever, has been used in such simulations of actual car travel driving. Thus, when car travel is referred to herein, the reader will understand that operation of the car on a chassis dynamometer is referred to, and not actual travel of the car as on a roadway.
However, in order to conduct a simulated driving in an appointed travelling pattern of the motorcar by means of such a robot, it is required to suitably choose a gain of an accelerator-controlling system (hereinafter referred to as an accelerator gain). But, disadvantages occur in that an oscillation is produced in signals in such a controlling system to make stabilized driving impossible if the accelerator gain is set at too high of a value. On the other hand, an aim of the appointed motorcar travelling pattern cannot be achieved if the accelerator gain is set at a lower value.
Further, with conventional automobile driving simulation robots accelerations and decelerations of the automobile under test have been repeated to observe the stability of response characteristics in the case where the accelerator gain is changed, thus determining the optimum accelerator gain for every gear-shift position (for example a first gearshift position, a second gear-shift position and the like) by the trial and error method.
However, according to the above described conventional controlling method, disadvantages have occurred in that it requires great skill to determine the accelerator gain, so that not only a considerably long time is required for obtaining the optimum accelerator gain but also an individual difference is produced in the obtained accelerator gain. That is, the accuracy and repeatability of the test results are affected by the skill of the person determining the accelerator gain.